TY - JOUR
T1 - The role of heat shock protein 70 in vitamin D receptor function
AU - Lutz, Ward
AU - Kohno, Kenji
AU - Kumar, Rajiv
N1 - Funding Information:
Work was supported by NIH Grants (to R.K.) DK 25409, AR 27032, and DK 58546.
PY - 2001
Y1 - 2001
N2 - We previously demonstrated that the 1α,25-dihydroxyvitamin D3 receptor (VDR) interacts with the constitutive heat shock protein, hsc70 in vitro, and with DnaK (Biochem. Biophys. Res. Commun. 260, 446-452, 1999). The biological significance of VDR-heat shock protein interactions, however, is unknown. To examine the role of such interactions in eukaryotic cells, we heterologously expressed VDR and RXRα together with a vitamin D-responsive reporter system in Saccharomyces cerevisiae and examined the consequences of heat shock protein 70 gene (SSA) deletion in these cells. We show that heterologously expressed VDR associates with the yeast cytosolic hsp70 protein, Ssa1p. Deletion of the SSA2, SSA3, and SSA4 genes and reduction of Ssa1p activity, reduces the intracellular concentrations of the VDR and its heterodimeric partner, RXRα and reduces the activity of a vitamin D-dependent gene. Hsp70-like chaperone proteins play a role in controlling concentrations of the VDR within the cell.
AB - We previously demonstrated that the 1α,25-dihydroxyvitamin D3 receptor (VDR) interacts with the constitutive heat shock protein, hsc70 in vitro, and with DnaK (Biochem. Biophys. Res. Commun. 260, 446-452, 1999). The biological significance of VDR-heat shock protein interactions, however, is unknown. To examine the role of such interactions in eukaryotic cells, we heterologously expressed VDR and RXRα together with a vitamin D-responsive reporter system in Saccharomyces cerevisiae and examined the consequences of heat shock protein 70 gene (SSA) deletion in these cells. We show that heterologously expressed VDR associates with the yeast cytosolic hsp70 protein, Ssa1p. Deletion of the SSA2, SSA3, and SSA4 genes and reduction of Ssa1p activity, reduces the intracellular concentrations of the VDR and its heterodimeric partner, RXRα and reduces the activity of a vitamin D-dependent gene. Hsp70-like chaperone proteins play a role in controlling concentrations of the VDR within the cell.
KW - Chaperones
KW - Heat shock protein 70
KW - Vitamin D receptor
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U2 - 10.1006/bbrc.2001.4711
DO - 10.1006/bbrc.2001.4711
M3 - Article
C2 - 11302745
AN - SCOPUS:0034806815
SN - 0006-291X
VL - 282
SP - 1211
EP - 1219
JO - Biochemical and Biophysical Research Communications
JF - Biochemical and Biophysical Research Communications
IS - 5
ER -